//1. alloc
let buf = Buffer.alloc(10);
// console.log(buf);
//2. allocUnsafe
let buf_2  = Buffer.allocUnsafe(10);
console.log(buf_2);
//3. from
let buf_3 = Buffer.from('hello');
let buf_4 = Buffer.from([105, 108, 111, 118, 101, 121, 111, 117]);
console.log(buf_4);